Electric motor repair

Discussion in 'REME' started by Barrack Room Lawyer, Apr 8, 2009.

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  1. Apologies for posting this in here, but hey, if the REME cannot help me with this then no-one can!

    My 6 year old son has a electric quad bike which runs via x2 6v batteries.( standard kids ride on toy)

    Its been stood for the winter in the shed, I got it out to charge it the other day and left it for a good 20hr charge, however, when I turned it on to check it nothing happened, the solenoid clicks but the motor did not turn in either direction, I flicked the forward and rev button a couple of times and it started working in reverse, happy days.

    But it still will not run forwards, the solenoid clicks but the motor will not turn, I have checked all joints connections nothing seems lose, it only has 2 fuses on it, they are both ok, there do not seem to be any dampness anywhere either.

    If anyone has any idea what the cause could be I would be very grateful for any suggestions (my son even more so!)
  2. Get your batteries checked out, sounds like they are not holding a charge.
  3. If it runs alright in reverse then batteries are ok. If it just goes a little bit could be the batteries (lower gearing in reverse).
  4. Check the motor for easy of movement, by hand. It should move easily.
  5. You don't really believe that, do you?

    My two pennorth: Corrosion on some contacts somewhere. The bike may not be damp now, but it will have been several times during the winter allowing verdegris or oxides to form on copper surfaces.

    Repeated operation of the switches may clear the problem - just like it did to get reverse working. Persevere.
  6. Hit it with a hammer. If nothing else, you can exorcise thoes deamons :)
  7. Remember, these things are built to a price, not to a standard.

    How old is it? Rechargeable batteries (especially in cars) are lasting longer these days - as mentioned above, the weak points are the switch contacts. Strip the forward/reverse switch down and caress the contacts with a fine file (nail file?) or emery cloth, if you can, tin the contacts with solder.

    When I had Peugeots, I had incredible problems with corrosion in the rear light clusters - water would get in and gradually oxidise the contacts, it was a bugger to clean the crap off.

    Edited twice due to lack of alcohol and crap punctuation.
  8. Jeez,

    One thinks it's the batteries when clearly it goes OK in reverse, another thinks it has a gearbox with different forward/reverse ratios when it has no more than a 12V power source, I blame the death of the sparky trade!

    Contacts, wait out........
  9. Dying trade Mr ee, not a dead trade yet.
    But i'd agrre with you on the issue of contacts. BRL, i'd care to wager it's one of your sets of contacts. Either on the switch (most likely) or at the solenoid, where, depending on which way you operate the switch, the direction which current flows through the motor is controlled. Try swapping wires at the switch to see if it does indeed go forward when selecting reverse. (this confirms faulty switch.

    Simple really. Failing that it looks like little BRL might be getting a new quad.
  10. Superb advice there sir, it is indeed a faulty switch, swapped the red and black around and hey presto it runs forward, it looks like a trip to maplins is in order!

    Thanks for all the superb advice, hints tips and tricks fellas!